Battery pack

ABSTRACT

A battery pack includes a battery cell having an electrode tab and a protective circuit module electrically connected to the electrode tab. The protective circuit module has a first surface in an assembling direction of the electrode tab and a second surface opposite the first surface. The electrode tab is separated from the first surface. Therefore, the battery pack has an improved connection structure between the battery cell and the protective circuit module, and short circuits can be prevented or substantially prevented.

CROSS-REFERENCE TO RELATED APPLICATION

This application claims priority to and the benefit of Korean PatentApplication No. 10-2014-0130325, filed on Sep. 29, 2014, in the KoreanIntellectual Property Office, the entire content of which isincorporated herein by reference.

BACKGROUND

1. Field

Aspects of one or more embodiments relate to a battery pack.

2. Description of the Related Art

Along with the development of wireless Internet and communicationtechnology, the use of portable computers such as tablet personalcomputers (PCs) or laptop computers equipped with batteries instead ofother power supplies has become widespread. Portable computers aresmall, easy-to-carry, and optimized in terms of mobility, and thus arewidely used for business and personal use.

Portable computers including built-in battery packs may be freely usedeven when a power outlet is not available. A battery pack in which manyrechargeable battery cells are electrically connected to each other inthe form of a module may function as a high-capacity, high-power powersupply. In this case, the battery pack may include a protective circuitmodule for electrically connecting the battery cells and controllingcharging and discharging operations of the battery cells.

SUMMARY

Aspects of one or more exemplary embodiments are directed toward abattery pack having an improved connection structure between a batterycell and a protective circuit module for preventing or substantiallypreventing a short circuit.

Additional aspects will be set forth in or will be apparent from in thedescription which follows or may be learned by practice of the presentedembodiments.

According to one or more exemplary embodiments, a battery pack includes:a battery cell including an electrode tab; and a protective circuitmodule electrically connected to the electrode tab, the protectivecircuit module including a first surface in an assembling direction ofthe electrode tab and a second surface opposite the first surface,wherein the electrode tab is separated from the first surface.

A connection tab may be positioned across a connection slot of theprotective circuit module, and the electrode tab may be on and welded toan upper surface of the connection tab when viewed from the assemblingdirection.

The connection slot may extend inward from an edge of the protectivecircuit module to a position away from the electrode tab.

The connection slot may define a gap between the first surface of theprotective circuit module and the electrode tab.

The connection tab may be bent in a depth direction of the connectionslot.

The connection tab may include: wings on both sides of the connectiontab and located at peripheral sides of the connection slot; and asupport portion between the wings and bent in the depth direction of theconnection slot.

The support portion may be at a position separated from the firstsurface of the protective circuit module in the depth direction of theconnection slot, and the electrode tab may be on the support portion.

A connection tab may be positioned across a connection slot of theprotective circuit module, and the electrode tab may be on an uppersurface of the connection tab, wherein an end portion of the electrodetab may be bent through the connection slot to surround an edge of theconnection tab.

A bent portion of the electrode tab may be an innermost portion of theelectrode tab in a direction toward the interior of the protectivecircuit module, and the connection slot may define a gap between thebent portion of the electrode tab and the first surface of theprotective circuit module.

BRIEF DESCRIPTION OF THE DRAWINGS

These and/or other aspects will become apparent and more readilyappreciated from the following description of the exemplary embodiments,taken in conjunction with the accompanying drawings in which:

FIG. 1 is an exploded perspective view illustrating a battery packaccording to an exemplary embodiment;

FIGS. 2A and 2B are views illustrating details of a connection structurebetween a battery cell and a protective circuit module illustrated inFIG. 1;

FIG. 3 is a view illustrating a connection structure between a batterycell and a protective circuit module according to another exemplaryembodiment;

FIGS. 4A and 4B are views illustrating a connection structure between abattery cell and a protective circuit module according to anotherexemplary embodiment; and

FIGS. 5A and 5B are views illustrating a connection structure between abattery cell and a protective circuit module according to anotherexemplary embodiment.

DETAILED DESCRIPTION

Reference will now be made in detail to exemplary embodiments, examplesof which are illustrated in the accompanying drawings, wherein likereference numerals refer to like elements throughout. In this regard,the present exemplary embodiments may have different forms and shouldnot be construed as being limited to the descriptions set forth herein.Accordingly, the exemplary embodiments are merely described below, byreferring to the figures, to explain aspects of the present description.As used herein, the term “and/or” includes any and all combinations ofone or more of the associated listed items.

It will be understood that, although the terms “first”, “second”,“third”, etc., may be used herein to describe various elements,components, regions, layers and/or sections, these elements, components,regions, layers and/or sections should not be limited by these terms.These terms are only used to distinguish one element, component, region,layer or section from another element, component, region, layer orsection. Thus, a first element, component, region, layer or sectiondiscussed below could be termed a second element, component, region,layer or section, without departing from the spirit and scope of theinventive concept.

Expressions such as “at least one of,” when preceding a list ofelements, modify the entire list of elements and do not modify theindividual elements of the list. Further, the use of “may” whendescribing embodiments of the present invention refers to “one or moreembodiments of the present invention.”

When a first element is described as being “coupled” or “connected” to asecond element, the first element may be directly “coupled” or“connected” to the second element, or one or more other interveningelements may be located between the first element and the secondelement.

Spatially relative terms, such as “beneath”, “below”, “lower”,“downward”, “above”, “upper” and the like, may be used herein for easeof description to describe one element or feature's relationship toanother element(s) or feature(s) as illustrated in the figures. It willbe understood that the spatially relative terms are intended toencompass different orientations of the device in use or operation inaddition to the orientation depicted in the figures. For example, if thedevice in the figures is turned over, elements described as “below” or“beneath” other elements or features would then be oriented “above” theother elements or features. Thus, the exemplary term “below” canencompass both an orientation of above and below. The device may beotherwise oriented (rotated 90 degrees or at other orientations) and thespatially relative descriptors used herein interpreted accordingly.

A battery pack will now be described in detail with reference to theaccompanying drawings, in which exemplary embodiments are shown.

FIG. 1 is an exploded perspective view illustrating a battery packaccording to an exemplary embodiment.

Referring to FIG. 1, the battery pack includes battery cells 200, aframe 100 supporting the battery cells 200, and a protective circuitmodule 400 supported on the frame 100 together with the battery cells200 and controlling charging and discharging operations of the batterycells 200.

Each of the battery cells 200 may include an electrode assembly and apouch 205 sealing the electrode assembly. For example, the electrodeassembly may be manufactured by forming a stack including a positiveelectrode plate coated with a positive electrode active material, anegative electrode plate coated with a negative electrode activematerial, and a separator between the positive and negative electrodeplates, and winding the stack in the form of a jelly roll.Alternatively, the electrode assembly may be manufactured by repeatedlystacking a positive electrode plate, a separator, and a negativeelectrode plate.

First and second electrode tabs 212 and 213 having different polaritiesmay be connected to the electrode assembly. The first and secondelectrode tabs 212 and 213 may protrude outward through a side of thebattery cell 200 and be electrically connected to the protective circuitmodule 400, as described later. In the present disclosure, the first andsecond electrode tabs 212 and 213 may be collectively referred to as anelectrode tab 210. For example, the electrode tab 210 may be referred toas a term including one of the first and second electrode tabs 212 and213 or both of the first and second electrode tabs 212 and 213.

The battery cells 200 may be electrically connected in series, parallel,or series-parallel through the protective circuit module 400. Thebattery cells 200 may be electrically connected as a module by theprotective circuit module 400.

For example, the first and second electrode tabs 212 and 213 may beformed on a side of each of the battery cells 200. In this case, theprotective circuit module 400 may extend across the sides of the batterycells 200 and may be electrically connected to the first and secondelectrode tabs 212 and 213 of the battery cells 200 neighboring eachother.

In the embodiment shown in FIG. 1, two battery cells 200 may be paired,and the battery cells 200 may be arranged in such a manner that theelectrode tabs 210 of each pair of the battery cells 200 may face theelectrode tabs 210 of the other pair of battery cells 200.

In another embodiment, the battery cells 200 may be arranged in parallelwith each other, and the first and second electrode tabs 212 and 213 mayextend in parallel with each other from the battery cells 200 to a sideof the protective circuit module 400.

The protective circuit module 400 may measure state variables such astemperatures, voltages, or currents of the battery cells 200 formonitoring the operations of the battery cells 200 and may function as acontrol unit for controlling charging and discharging operations of thebattery cells 200 based on results of the monitored variables.

For example, a discharge current collected from the battery cells 200may be input to the protective circuit module 400 and then may besupplied to an external device. For this, a connector 450 may beconnected to the protective circuit module 400 for electric connectionto the external device. For example, the connector 450 may include aplurality of connection lines.

For example, the battery pack may be included in the external device asa power supply and may be electrically connected to the external devicethrough the connector 450 which includes the connection lines for signaland power transmission. An electrical connector 460 may be provided atan end of the connector 450 for electric connection to the externaldevice.

The frame 100 forms an overall framework of the battery pack andsupports the battery cells 200 and the protective circuit module 400.The frame 100 may be a member capable of supporting two or more batterycells 200.

Cell rests G may be formed in the frame 100 for accommodating thebattery cells 200. The cell rests G may have a recess shape and maydefine installation positions of the battery cells 200. For example, thecell rests G may define the installation positions of the battery cells200 together with barrier walls 100 a formed along edges of the frame100 to surround the cell rests G. The cell rests G may have a recessshape corresponding to the shape of the battery cells 200.

A circuit rest B may be formed in the frame 100 for accommodating theprotective circuit module 400. The circuit rest B may have a recessshape corresponding to the shape of the protective circuit module 400.

For example, the circuit rest B may be formed approximately (or about)in the middle of the frame 100, and the cell rests G may be formed onboth sides of the circuit rest B. Since the protective circuit module400 is electrically connected to the battery cells 200, if theprotective circuit module 400 is at a center position, electricconnection passages may be shortened.

The cell rests G and the circuit rest B may be separated from each otherby barrier walls 100 a extending across the frame 100, and the batterycells 200 and the protective circuit module 400 accommodated in the cellrests G and the circuit rest B may be electrically connected to eachother without mechanically interfering with neighboring structures.

Reinforcing parts may be formed on the frame 100. The reinforcing partsmay include a plurality of ribs. For example, the reinforcing parts mayinclude a plurality of parallel ribs extending on the frame 100 in onedirection. Owing to the reinforcing parts, although the weight of theframe 100 is reduced, the frame 100 may have a sufficient degree ofmechanical rigidity for resisting bending or twisting.

For example, the barrier walls 100 a defining the cell rests G and thecircuit rest B may extend along the edges of the frame 100 or across theframe 100 and thus may function as reinforcing parts improving themechanical strength of the frame 100. The frame 100 may be formed of aninsulative resin by an injection molding method. However, the presentinvention is not limited thereto.

The frame 100 may include a first surface 101 and a second surface 102.For example, the battery cells 200 and the protective circuit module 400may be coupled to the first surface 101 of the frame 100. For example,the first and second surfaces 101 and 102 refer to main surfaces of theframe 100 and may occupy the largest areas of the frame 100 having anapproximately (or about) rectangular parallelepiped shape.

The battery pack illustrated in FIG. 1 as an example may include aninsulation plate 300 to cover the first surface 101 of the frame 100.The insulation plate 300 may cover the first surface 101 of the frame100 so that the battery cells 200 may not be separated from the frame100. For example, after the battery cells 200 are on the frame 100, theinsulation plate 300 may cover the battery cells 200 to prevent orsubstantially prevent separation of the battery cells 200. The positionsof the battery cells 200 on the frame 100 may be securely fixed owing tothe insulation plate 300 above the first surface 101 of the frame 100.

The insulation plate 300 may be coupled to or bonded to the frame 100.The insulation plate 300 may be formed in a plate shape by using aninsulative material such as polyethylene terephthalate (PET).

The battery cells 200 are electrically connected to the protectivecircuit module 400. The battery cells 200 are electrically connected tothe protective circuit module 400 through connection structures P.

FIGS. 2A and 2B are views illustrating details of the connectionstructure P between one of the battery cells 200 and the protectivecircuit module 400 illustrated in FIG. 1. Referring to FIGS. 2A and 2B,the electrode tab 210 of the battery cell 200 is electrically connectedto a connection tab 410 of the protective circuit module 400. Forexample, the electrode tab 210 of the battery cell 200 may be welded tothe connection tab 410 of the protective circuit module 400.

In some embodiments, the electrode tab 210 of the battery cell 200 maybe placed on the connection tab 410 of the protective circuit module 400and then may be welded thereto. In this case, the electrode tab 210 ofthe battery cell 200 and the connection tab 410 of the protectivecircuit module 400 may be welded together using a welding electrode inan overlapped state. For example, the welding electrode may accesswelding portions of the electrode tab 210 and the connection tab 410through upper and lower sides of the connection structure P. In someembodiments, the welding electrode may apply a welding current to anupper surface of the electrode tab 210 and a lower surface of theconnection tab 410 exposed through a connection slot 400′.

Since the lower surface of the connection tab 410 is exposed through theconnection slot 400′, the welding electrode may access the connectiontab 410. For example, the connection tab 410 of the protective circuitmodule 400 may be placed across an upper side of the connection slot400′, and then the electrode tab 210 of the battery cell 200 may bewelded to an upper surface of the connection tab 410.

In some embodiments, the connection slot 400′ may extend at least to aposition away from the electrode tab 210 of the battery cell 200. Then,owing to the connection slot 400′, a gap S (refer to FIG. 2B) may beformed between the electrode tab 210 and a first surface 401 of theprotective circuit module 400 on which various suitable circuit patternsmay be arranged.

For example, the protective circuit module 400 may have an approximately(or about) hexahedral shape, and the largest two main surfaces of theprotective circuit module 400, that is, upper and lower surfacesthereof, may be referred to as first and second surfaces 401 and 402.When viewed in an assembling direction of the electrode tab 210, thatis, when the electrode tab 210 is assembled in a direction toward theupper surface of the protective circuit module 400 as shown in FIG. 2A,the upper surface may be the first surface 401.

The connection slot 400′ may extend inward from an end of the protectivecircuit module 400 in a direction parallel with the electrode tab 210 toa position away from an end 211 of the electrode tab 210. Owing to thisstructure of the connection slot 400′, as described above, a gap S(refer to FIG. 2B) may be formed between the electrode tab 210 and thefirst surface 401 of the protective circuit module 400 on which varioussuitable circuit patterns may be arranged, and thus electric contactbetween the circuit patterns and the electrode tab 210 may be preventedor substantially prevented.

Both the electrode tab 210 of the battery cell 200 and the connectionslot 400′ may extend toward an inner side (or inner area) of theprotective circuit module 400, but the connection slot 400′ may furtherextend to a position away from the end 211 of the electrode tab 210 sothat the electrode tab 210 may not make contact with the first surface401 of the protective circuit module 400, thereby preventing orsubstantially preventing a short circuit between the electrode tab 210and the circuit patterns arranged on the first surface 401.

FIG. 3 is a view illustrating a connection structure between a batterycell 200 and a protective circuit module 400 according to anotherexemplary embodiment. Referring to FIG. 3, a connection tab 410 may beplaced on a connection slot 400′ of the protective circuit module 400,and an electrode tab 210′ of the battery cell 200 may be welded to anupper surface of the connection tab 410. That is, the connection tab 410and the electrode tab 210′ placed on one another may be welded together.In this case, an end portion of the electrode tab 210′ may be bent tosurround the connection tab 410.

The end portion of the electrode tab 210′ may be bent to surround anedge of the connection tab 410 through the connection slot 400′.Therefore, an innermost end portion 211′ of the electrode tab 210′ maybe separated from a first surface 401 of the protective circuit module400 with the connection slot 400′ therebetween. In some embodiments, theinnermost end portion 211′ of the electrode tab 210′, that is, an endportion of the electrode tab 210′ extending to an inner side (or innerarea) of the protective circuit module 400, may not be in contact withthe first surface 401 of the protective circuit module 400 because theelectrode tab 210′ is bent, and owing to the connection slot 400′, a gapS may be formed therebetween.

Since the innermost end portion 211′ of the electrode tab 210′ isseparated from the first surface 401 of the protective circuit module400 with the gap S therebetween, the electrode tab 210′ may not be shortcircuited with circuit patterns formed on the first surface 401.

As described with reference to FIGS. 2A and 2B, the connection slot 400′of the protective circuit module 400 of the current embodiment extendsto a position away from the electrode tab 210′. That is, both theconnection slot 400′ of the protective circuit module 400 and theelectrode tab 210′ of the battery cell 200 extend toward an inner side(or inner area) of the protective circuit module 400, wherein theconnection slot 400′ extends to a position away from the innermost endportion 211′ of the electrode tab 210′ of the battery cell 200.

In this case, since the electrode tab 210′ of the battery cell 200 isbent, although the connection slot 400′ does not extend too much (ordoes not extend relatively too much), the gap S may be sufficientlyformed between the first surface 401 of the protective circuit module400 and the innermost end portion 211′ of the electrode tab 210′. Forexample, if the electrode tab 210′ extends without being bent, theconnection slot 400′ may need to extend too far (or relatively too far)of a distance in order to be away from the electrode tab 210′.

In the current embodiment, a marginal portion of the electrode tab 210′is bent. Thus, the electrode tab 210′ does not extend inwardly too much(or does not extend inwardly relatively too much) and does not makecontact with the first surface 401 of the protective circuit module 400on which the circuit patterns are formed. As a result, a short circuitbetween the electrode tab 210′ and the circuit patterns may be preventedor substantially prevented.

To prevent or substantially prevent a short circuit with the protectivecircuit module 400 (that is, the circuit patterns formed on the firstsurface 401 of the protective circuit module 400), the length of theelectrode tab 210′ may be checked, for example, through a strict processcontrol. In the current embodiment, however, the length of the electrodetab 210′ may be checked with a relatively generous margin because themarginal portion of the electrode tab 210′ is bent to prevent orsubstantially prevent the electrode tab 210′ from extending too much (orrelatively too much). That is, although the length of the electrode tab210′ is not checked through a strict process control, a short circuitbetween the electrode tab 210′ and the protective circuit module 400 maybe prevented or substantially prevented.

FIGS. 4A and 4B are views illustrating a connection structure between abattery cell 200 and a protective circuit module 400 according toanother exemplary embodiment. Referring to FIGS. 4A and 4B, a connectiontab 410′ of the protective circuit module 400 may be placed across aconnection slot 400′ of the protective circuit module 400. In thisembodiment, the connection tab 410′ of the protective circuit module 400may be inserted in the depth direction (d) of the connection slot 400′.

An electrode tab 210 of the battery cell 200 is placed on an uppersurface of the connection tab 410′ inserted in the depth direction (d)of the connection slot 400′, and thus the electrode tab 210 of thebattery cell 200 is placed in the connection slot 400′. That is, sincethe electrode tab 210 is placed in the connection slot 400′, a gap S maybe formed between the electrode tab 210 and a first surface 401 of theprotective circuit module 400.

In some embodiments, the connection tab 410′ may include wings 411 onboth sides of the connection slot 400′, and a support portion 415between the wings 411 and bent from the wings 411 in the depth direction(d). Since the support portion 415 is lower than the wings 411 in thedepth direction (d), the electrode tab 210 of the battery cell 200placed on the support portion 415 is naturally separated from the firstsurface 401 of the protective circuit module 400 in the depth direction(d).

For example, the gap S may be properly formed in the depth direction (d)from the upper surface of the electrode tab 210 of the battery cell 200to the first surface 401 of the protective circuit module 400. Owing tothe gap S, the electrode tab 210 of the battery cell 200 may be properlyseparated from the first surface 401 of the protective circuit module400 on which circuit patterns are formed, and thus a short circuitbetween the electrode tab 210 and the circuit patterns may be preventedor substantially prevented.

FIGS. 5A and 5B are views illustrating a connection structure between abattery cell 200 and a protective circuit module 400 according toanother exemplary embodiment. Referring to FIGS. 5A and 5B, a connectiontab 410′ is placed across a connection slot 400′ of the protectivecircuit module 400, and a portion of the connection tab 410′ is insertedin a depth direction (d) of the connection slot 400′. Then, an electrodetab 210′ of the battery cell 200 is welded to an upper surface of theconnection tab 410′.

In this embodiment, the electrode tab 210′ overlaps the upper surface ofthe connection tab 410′ and is bent to surround an edge of theconnection tab 410′. That is, a marginal portion of the electrode tab210′ may be bent, and a first gap S1 (as shown in FIG. 5B) may be formedbetween an innermost end portion 211′ of the electrode tab 210′ and afirst surface 401 of the protective circuit module 400. In other words,the connection slot 400′ of the protective circuit module 400 may extendfurther from the innermost end portion 211′ of the electrode tab 210′into the protective circuit module 400, and the first gap S1 may beformed between the innermost end portion 211′ of the electrode tab 210′and the first surface 401 of the protective circuit module 400.

In this case, since the marginal portion of the electrode tab 210′ isbent, the electrode tab 210′ may not extend excessively far (orrelatively excessively far) into an inner side (or inner area) of theprotective circuit module 400 and thus may not be short circuited withthe protective circuit module 400. For example, the length of theelectrode tab 210′ may be strictly checked for preventing orsubstantially preventing a short circuit with the protective circuitmodule 400. In the current embodiment, however, since the marginalportion of the electrode tab 210′ is bent, although the length of theelectrode tab 210′ may vary within a generous margin, the electrode tab210′ may still not be short circuited with the protective circuit module400.

Referring to FIG. 5B, in addition to the first gap S1, a second gap S2may be formed between the electrode tab 210′ and the first surface 401of the protective circuit module 400. The gap S2 is formed because asupport portion 415 of the connection tab 410′ is inserted in the depthdirection (d) of the connection slot 400′. In some embodiments, becausethe electrode tab 210′ is supported on the support portion 415 formedbetween a pair of wings 411 and inserted in the depth direction (d) ofthe connection slot 400′, the gap S2 may be formed between the electrodetab 210′ and the protective circuit module 400 in the depth direction(d).

As described above, according to the one or more of the above exemplaryembodiments, the protective circuit module for electrically connectingthe battery cells, for providing charging and discharging currentpassages, and/or for controlling charging and discharging operations isconfigured to have an improved connection structure, and thus a shortcircuit between the protective circuit module and the battery cells maybe prevented or substantially prevented.

It should be understood that the exemplary embodiments described hereinshould be considered in a descriptive sense only and not for purposes oflimitation. Descriptions of features or aspects within each exemplaryembodiment should typically be considered as available for other similarfeatures or aspects in other exemplary embodiments.

While one or more exemplary embodiments have been described withreference to the figures, it will be understood by those of ordinaryskill in the art that various changes in form and details may be madetherein without departing from the spirit and scope as defined by thefollowing claims and their respective equivalents.

What is claimed is:
 1. A battery pack comprising: a battery cell comprising an electrode tab; and a protective circuit module electrically connected to the electrode tab, the protective circuit module comprising a first surface configured to face the electrode tab and a second surface opposite the first surface, wherein the electrode tab is separated from the first surface; and wherein a connection tab is positioned across a connection slot of the protective circuit module, and the electrode tab is on an upper surface of the connection tab, and wherein an end portion of the electrode tab is bent through the connection slot to surround an edge of the connection tab.
 2. The battery pack of claim 1, wherein the electrode tab is on and coupled to a surface of the connection tab facing the electrode tab.
 3. The battery pack of claim 2, wherein the connection slot extends inward from an edge of the protective circuit module to a position away from the electrode tab.
 4. The battery pack of claim 3, wherein the connection slot defines a gap between the first surface of the protective circuit module and the electrode tab.
 5. The battery pack of claim 2, wherein the connection tab is bent in a depth direction of the connection slot.
 6. The battery pack of claim 5, wherein the connection tab comprises: wings on both sides of the connection tab and located at peripheral sides of the connection slot; and a support between the wings and bent in the depth direction of the connection slot.
 7. The battery pack of claim 6, wherein the support is at a position separated from the first surface of the protective circuit module in the depth direction of the connection slot, and wherein the electrode tab is placed on the support.
 8. The battery pack of claim 1, wherein a bent portion of the electrode tab is an innermost portion of the electrode tab in a direction toward the interior of the protective circuit module, and the connection slot defines a gap between the bent portion of the electrode tab and the first surface of the protective circuit module. 